Electromagnetic field exposure affects the calling song, phonotaxis, and level of biogenic amines in crickets

Abstract

AbstractElectromagnetic field (EMF) is ubiquitous in the environment, constituting a well-known, but poorly understood stressor. Few studies have been conducted on insect responses to EMF, although they are an excellent experimental model and are of great ecological importance. In our work, we tested the effects of EMF (50 Hz, 7 mT) on the cricketGryllus bimaculatus: the male calling song pattern, female mate choice and levels of biogenic amines in the brain. Exposure of males to EMF modified the number and period of chips in their calling song, but not the sound frequency. Aged (3-weeks-old) females were attracted to both natural and EMF-modified male signals, whereas young (1-week-old, virgin) females responded only to the modified signal, suggesting its higher attractance. A stress response of males to EMF may be responsible for the change in the calling song, as suggested by changes in the amine levels in their brains (an increase in dopamine, tyrosine, and serotonin concentration and a decrease in octopamine level). These findings indicate thatG. bimaculatusresponds to EMF like to stressful conditions, which may change the condition and fitness of exposed individuals, disrupt mate selection and, in consequence, affect the species existence.